Crimping apparatus



Feb. 14, 1956 w. D. HAY

CRIMPING APPARATUS 2 Sheets-Sheet 1 Filed Oct. 28, 1952 INI LNIOR.14/444 MM 0. //A Y.

Feb. 14, 1956 w. D. HAY 2,734,228

CRIMPING APPARATUS Filed Oct. 28, 1952 2 Sheets-Sheet 2 45 INVENTOR. 6A3 MLL/AM 0. #nx

ATTORNEY CRIMPING APPARATUS William D. Hay, Peekskill, N. Y., assignorto Alexander Smith, Incorporated, White Plains, N. Y., a corporation ofNew York Application October 28, 1952, Serial No. 317,238

10 Claims. (Cl. 19--66) This invention relates to an apparatus forcrimping continuous filament tow or yarn and particularly tow or yarnmade from synthetic thermoplastic materials such as organic derivativesof cellulose, linear polyamides (nylon,

' Orlon), polyesters (Dacron), vinylidene chloride (Saran),

acrylic fibers (Orlon), vinyl acetate-chloride copolymers (Vinyon), andothers having similar characteristics. The invention is also useful forcrimping other fibers in filament or staple form, for example wool,vegetable fibers, and the like.

An object of this invention is to provide a crimper of the stutter boxtype which is particularly adapted for use with such small denier tow oryarn.

Another object is to provide a crimping apparatus of the above typehaving novel and improved heating means for maintaining the tow or yarnat the proper temperature for crimping.

Other objects and advantages will be apparent as the nature of theinvention is more fully disclosed.

The nature of this invention will be better understood by referring tothe following description, taken in connection with the accompanyingdrawings, in which specific embodiments thereof have been set forth forpurposes of illustration.

In the drawings:

Fig. 1 is a diagrammatic view, partly in section, of a crimpingapparatus embodying the present invention;

Fig. 2 is a perspective view of the block forming the crimping chamber;

Fig. 3 is a vertical section taken on the line 3-3 of Fig. 2;

Fig. 4 is a sectional detail showing a modified form of discharge gatefor the crimping chamber; 7

Fig. 5 is a detail view showing the mounting of the feed rollers of Fig.l, but on a larger scale;

Fig. 6 is a vertical section through the feed rollers taken on the line6--6 of Fig. 7; I

Fig. 7 is a horizontal section taken on the line 7-7 of Fig. 6; and

Figs. 8, 9 and 10 are detail views illustrating different forms ofdischarge gates.

Referring to the drawings more in detail, the crimper is shown ascomprising a pair of feed rolls 10 and 11 which are adapted to feed acontinuous filament tow or yarn 12 into a crimping chamber 13 formed ina block 14. The feed roll 10 is mounted on a shaft 15 carrying a drivinggear 16 meshing with a driving pinion 17. The shaft 15 and the pinion 17are mounted on a bracket 18 projecting from a base 19. The feed roll 11is mounted on a shaft 20 which is journaled in bearings 21 in a housing22 carried by arms 23 pivoted to a fixed pin 24 mounted in brackets 25which project upwardly from the base 19. A spring 26 engages an arm 23to hold the feed roll 11 in pressure engagement with the feed roll 10.Spring 26 is adjusted by means of a threaded pin 27 carried by a bracket28 also supported by the base 19. The shaft 20 carries a gear 29 meshingwith the gear 16 for driving the two feed rolls 10 and 11 in unison. Thegears 16 and nited States Patent 0 2,734,223 Patented Feb. 14, 1956 ice29 are provided with teeth which are of sufiicient depth to remain indriving engagement throughout the limited range of movement of the arms23 encountered in normal operation.

The block 14 is supported below the feed rolls 10 and 11 by a clamp 30attached to the bracket 18. In addition to the central tapered bore 13forming the crimping chamber the block 14 has a pair of bores 33 (Figs.2 and 3) extending parallel to the bore 13 and carrying heating units34, such as Calrods, by which the crimping chamber may be heated.

In order to permit the passage of a heating or setting fluid such as hotair through the crimping chamber apair. of manifolds 36 and 37 aremounted on opposite sides of the block 14 and communicate with passages38 and 39 respectively passing through the walls of the block .14 intothe bore 13. Inlet and outlet ducts 40 and 41 con nect respectively withthe manifolds 36 and 37. Ba'ffies 42 and 43 are shown as providedopposite the ducts 40 and 41 fordistributin g thefluid uniformlyin themanifolds.

At its upper end the block 14 is formed with a saddle comprising apairof channels formed by-side walls-45am arcuate walls 46. The side walls'45 are tangent to the cylindricalsurface of the bore 13 atdiametrically opposite sides and the arcuate walls 46 intersect the bore13 along a curve 47 to form a curved knife edge which extends around theperiphery of the bore- 13. The feed rolls 1i) and 1 1 conform in widthto the diameter of the bore 13 and the width of the channel and have aclose running fit with the =arcuate walls '46 adjacent the knife edges47. The walls 46 are curved to taper away from the periphery of therolls toward the outer surface of the block 14 so as to leave aclearance and thus reduce thefriction on the rollsand to facilitate thewearing in of the surfaces by the rolls to provide a close fit at theknife edge 47. Theside walls 45 project along the sides of the rolls 10and 11 so as to confine the tow or yarn against lateral displacement asit is fed by the feed rolls '10 and 11 into the crimping chamber. Thesmooth curve of the knife edge 47 which merges into the side walls 45 atthe entrance end of the crimping chamber avoids the formation of anycorners or projections which could interfere with or damage the tow oryarn as it is fed into the crimping chamber by feedrolls 10 and-11.

The block 14 is provided with a flange 50 at the exit end of thecrimping chamber formed by 'the bore 13. In the form shown in Fig. 1 atapered tube "51 is attached to the flange 50 by a sleeve 52. The 'tube51 may be made of glass or other smooth material and tapers toward itsdischarge end to an opening 53 whichconforrns in general to the size ofthe tow or yarn 12 which is being treated in the crimping chamber.

The tow or yarn '12 is shown as passing through a longitudinal slot orgroove 55 in a bar'56 which isprovidecl with suitable heating meansindicated as Calrods 57 and may have suitable heat insulation 58therear'ound. The tow or yarn 12 is preheated in passing through theslot 55 and then feeds around a roller 60 through-'a'tube 61 to the feedrolls 1i) and 11. Thetube '61 is mounted in a clamp 62 attached to thebracket 18, has a bore 63 of a size conforming generally to the size ofthe tow or yarn 12 and is positioned to guide the tow or yarn Fosterwinder which includes a driving roll 68 driven at a constant speed onwhich a cone winding 69 rests. The roll 68 is provided with traversingguide means 70 for guiding the tow or yarn into uniform layers and, dueto its constant peripheral speed of rotation, winds the entire packageunder a substantially constant tension which is controllable by thetension device 66. Although any other standard type of winder may beused it is preferable to use a constant speed winder for the reasons tobe described.

In the operation of this device the tow or yarn 12, which may forexample be composed of a bundle of fine filaments of syntheticthermoplastic material, is first passed through the preheating device toheat the material to a temperature somewhat below the temperature required for crimping, but sufficiently high to provide for substantiallyinstantaneous heating to the required temperature when the tow or yarnreaches the crimping chamber. The preheated tow or yarn is then fedthrough the guide tube 61 to the feed rolls and 11 and is gripped by thefeed rolls and forced into the mass of filaments packed in said chamber,thereby causing the tow or yarn to fold over and form fine crimps, thefineness and frequency of which depends upon the nature of the materialand the back pressure which is maintained in the crimping chamber. Ifthe material is preheated to or near the softening temperature thecrimps will be finer and of greater frequency than if the material isless highly preheated and is stiffer as it is forced into the crimpingchamber.

In order to maintain the crimping chamber at the proper temperature heatis supplied by a heating means shown as Calrods 34 which heat the wallsof the block 14 and thus transfer heat to the bore 13 and the materialtherein as it passes along the heated walls. This temperature may becontrolled by suitable thermostatic means not shown.

In order to remove moisture which may be driven 01f due to the heatmaintained in the crimping chamber, a fluid, such as hot air, may besupplied through the inlet duct 40 and the passages 38 into the chamber13 and may be removed through the passages 39 and outlet duct 41. Thisfluid may pick up heat from the walls and transfer the heat to thematerial within the crimping chamber or it may be preheated or ifdesired may carry a chemical softening or setting agent. Under certainconditions it may be sufficient to heat the material within the crimpingchamber by the hot fluid supplied through the duct 40 without heatingthe walls themselves, in which event the Calrods or the like 34 may beomitted.

The material is caused to remain in the crimping chamher a suflicientlength of time for the internal stresses produced by crimping to berelieved so that the tendency for the crimps to be opened up after thematerial has been removed from the chamber is eliminated. The ma terialimmediately cools and becomes permanently set upon removal from thecrimping chamber or the chamber may be so designed that the materialcools while packed in the tube 51 to a temperature below that at whichthere is any tendency for plastic flow. Since the stresses have beenrelieved by maintaining the material in heated condition in the crimpingchamber the crimp is permanently set by this heating and coolingoperation.

The pressure within the crimping chamber is determined by the rate ofremoval of the crimped tow or yarn from the tube 51. This in turn isdetermined by the rate at which the winder 67 is operated. The speed ofthe winder 67 is so adjusted and maintained with respect to the speed ofthe rolls 10 and 11 that selected conditions are maintained within thecrimping chamber. Since the tow or yarn is in a straight condition as itis fed by the rolls 10 and 11 into the crimping chamber and is incrimped condition as it leaves the chamber, the speed of the winder 67is correspondingly less than the speed of the rolls 10 and 11. Thetension applied to the tow or yarn by the winder 67 by varying theextension of the spring-like crimps determines the rate at which the towor yarn is withdrawn from the crimping chamber, which together with thephysical characteristics of the material determines the crimp frequencyand amplitude. The provision of a controlled rate of discharge as wellas a controlled rate of feed establishes a uniform operation and permitsthe nature of the crimp, the temperature and time within the crimpingchamber, and the rate of feed to be regulated with extreme accuracy.

In the embodiment of the invention illustrated in Fig. 4 the tube 51 atthe discharge end of the crimping chamber is shown as replaced by a tube75 which is at tached to the flange 50 and is provided with a bore 76through which the crimped material is discharged. The lower end of thetube 75 is split and a part of the wall at such lower end is formed by agate member 77 which is pivotally attached by a pivot 78 to brackets 79so as to swing inwardly for maintaining pressure against the material asit is fed through the bore, but to swing outwardly in response to thepressure of said material so as to allow the material to be releasedwhen the pressure reaches a predetermined value. The pressure thusexerted on the material by the gate member 77 is controlled by a block80 which is pivoted at 81 to the bracket 79 and is provided with aspring-pressed ball 82 hearing against the surface of the gate member77. The force exerted by the ball 82 is adjusted by means of a weight 83which is attached to a rod 84 carried by the block 80. In this way afine adjustment may be made of the force exerted by the gate member 77against the material in the bore 76. The operation of the crimpingchamber with this discharge gate is similar to that above describedexcept that the material is discharged due to the pressure produced bythe rolls 10 and 11 instead of being pulled from the chamber by awinding device.

Fig. 8 shows a modified form of gate including a hinge plate 88 pivotedat 89 to a wall 90 of a tubular member 91 which is attached to theflange 50. A weight 92, which may be adjustable, determines the forceexerted by the hinge plate 88 against the material within the crimpingchamber.

In the form shown in Fig. 9 a discharge gate is shown in the form of aflexible tube 95 which may be made of rubber or the like and is disposedon the flange 50 of Fig. l. The tube 95 is restricted at its dischargeend and the opening may be varied by a lever 96 bearing against the wallof the tube 95 and carrying a weight 97.

In the form shown in Fig. 10 a collar 100 is adapted to be attached tothe flange 50 by a set screw 101 and carries a set of spring fingers 102through which the tow or yarn feeds.

The pressure maintained within the crimping chamber in any of theseforms is determined by the force exerted by the movable gate at thedischarge end. The embodiments of Figs. 4, 8, 9 and 10 may be used incases where simplicity is required and where the nature of the materialis such that it is not necessary to provide feeding means as in Fig. 1for withdrawing the material from the crimping chamber.

Although certain embodiments of the invention have been shown anddescribed for purposes of illustration, it is to be understood that theinvention may be applied to various uses and that changes andmodifications may be made therein as will be apparent to a personskilled in the art.

What is claimed is:

1. An apparatus for crimping tow or yarn, comprising a pair of feedrolls adapted to feed said tow or yarn therebetween, a member having abore forming a crimping chamber, said member having at one end a saddleconforming to the bight of said rolls and having at the other end a tubehaving a bore tapering to a small opening at its discharge end.

2. An apparatus for crimping tow or yarn, comprise ing a pair of feedrolls adapted to feed said tow or yarn therebetween, a member having abore forming a crimping chamber disposed to rective the tow or yarn fromsaid rolls, said chamber being flared for a portion of its length fromsaid rolls and being tapered for the remainder of its length to arestricted opening at the discharge end.

3. An apparatus for crimping tow or yarn, comprising a pair of feedrolls adapted to feed said tow or yarn therebetween, a member having abore forming a crimping chamber disposed to receive the tow or yarn fromsaid rolls and a guide member having a passage for said tow or yarndisposed in advance of said rolls and having a surface conforming to thebight of said rolls for guiding the tow or yarn as it is gripped by saidrolls.

4. An apparatus for crimping tow or yarn, comprising a pair of feedrolls adapted to feed said tow or yarn therebetween, a member having abore forming a crimping chamber disposed to receive the tow or yarn fromsaid rolls, and a gate disposed at the discharge end of said chamber,said gate comprising a flexible member having a constricted opening forthe passage of the tow or yarn therethrough.

5. An apparatus for crimping tow or yarn, comprising a pair of feedrolls adapted to feed said tow or yarn therebetween, a member having abore forming a crimping chamber disposed to receive the tow or yarn fromsaid rolls, and a gate disposed at the discharge end of said chamber,said gate comprising a tapered flexible tube having a restricted openingfor the passage of the tow or yarn therethrough and being expandible dueto the force exerted thereon by the tow or yarn.

6. An apparatus for crimping tow or yarn, comprising a pair of feedrolls adapted to feed said tow or yarn therebetween, a member having abore forming a crimping chamber disposed to receive the tow or yarn fromsaid rolls, and a gate disposed at the discharge end of said chamber,said gate comprising a ring of flexible fingers having a restrictedopening for the passage of the tow or yarn therethrough and beingexpandible due to the force exerted thereon by the tow or yarn.

7. The method of crimping a tow or yarn which comprises feeding said towor yarn between feed rolls into a stufier crimper chamber containing amass of such tow or yarn under conditions to cause the tow or yarn totold and crimp as it is forced into said mass, heating the mass in saidchamber to a temperature and for a time to re lieve strains produced bycrimping, and pulling said crimped tow or yarn from said chamber undertension at a controlled rate.

8. The method of crimping a tow or yarn composed of continuous filamentsynthetic thermoplastic material which comprises preheating saidmaterial to a temperature near its softening point, feeding saidpreheated tow or yarn between feed rolls into a stufier crimper chambercontaining a mass of such filaments under conditions to cause thefilaments to fold and crimp as they are forced into said mass offilaments, heating the mass of filaments in said chamber to atemperature and for a time to relieve strains produced by crimping, andpulling said crimped tow or yarn from said chamber under tension at acontrolled rate.

9. The method of crimping a tow or yarn composed of continuous filamentsynthetic thermoplastic material which comprises feeding said tow oryarn between feed rolls into a stuffer cn'mper chamber containing a massof such tow or yarn under conditions to cause the tow or yarn to foldand crimp as it is forced into said mass, heating the mass of filamentsin said chamber to a temperature and for a time to relieve strainsproduced by crimping and pulling the crimped tow or yarn from saidchamber under tension at a controlled rate.

10. An apparatus for crimping tow or yarn, comprising a pair of feedrolls adapted to feed said tow or yarn therebetween, a member having abore forming a crimping chamber disposed to receive the tow or yarn fromsaid rolls, said chamber having a restricted passage at the dischargeend, and means pulling said tow or yarn from said discharge end throughsaid passage under tension.

References Cited in the file of this patent UNITED STATES PATENTS2,311,174 Hitt Feb. 16, 1943 2,514,557 Pfau July 11, 1950 2,575,781Barach Nov. 20, 1951 2,575,833 Pfau et al. Nov. 20, 1951 2,575,837Rainard Nov. 20, 1951 2,575,838 Rainard Nov. 20, 1951

